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Consider the following reactions at $1000\,^oC$
$(I)$ $Zn(s){\mkern 1mu} + {\mkern 1mu} 1/2{\mkern 1mu} {O_2}(g){\mkern 1mu} \xrightarrow{\Delta }{\mkern 1mu} ZnO(g){\mkern 1mu} ;$ $\Delta {G^o}{\mkern 1mu} = \,{\mkern 1mu} - \,{\mkern 1mu} 360\,{\mkern 1mu} {\mkern 1mu} kJ{\mkern 1mu} \,{\mkern 1mu} mo{l^{ - 1}}$
$(II)$ $C(s){\mkern 1mu} + {\mkern 1mu} 1/2{\mkern 1mu} {O_2}(g){\mkern 1mu} \xrightarrow{\Delta }{\mkern 1mu} CO(g){\mkern 1mu} ;$ $\Delta {G^o}{\mkern 1mu} = {\mkern 1mu} - \,{\mkern 1mu} 460{\mkern 1mu} {\mkern 1mu} \,kJ{\mkern 1mu} {\mkern 1mu} mo{l^{ - 1}}$
and choose the correct statement at $1000\,^oC$
$ZnO$ is more stable than $CO$
$ZnO$ can be reduced to $Zn$ by $C$
$ZnO$ and $CO$ are formed at equal rate
$ZnO$ can not be reduced to $Zn$ by $C$
Solution
From given reactions, Free energy of the reaction :
$ZnO(g)\, + \,C(s)\,\,\xrightarrow[{1000\,{\,^o}C\,}]{\Delta }\,Zn(g)\, + \,CO\,(g),$ is negative
